Investigation of the Mechanism of Alternative Promoters Influencing Alternative Splicing

It has been shown that splicing is coupled with transcription and other upstream and downstream processes. However, the detailed mechanism is far from being well understood. In this paper, we investigated the coupling of splicing and transcription by studying alternative splicing (AS) of human genes possessing alternative promoters (AP). It was found that AS occurs more often in AP-containing genes than in other genes. Moreover, it was observed that compared with AS in other genes, AS in AP-containing genes tend to appear as the type of alternative 5´ splice site and are more likely to influence 5´ UTR of mRNAs and N-terminal of protein products. These results suggest that AP possibly exert their influences mainly by controlling transcription elongation rate. Our work provides evidence for the coupling of AS and transcription and shed new light on the regulatory mechanism of AS.